speed.md +24 −0 added
1# Speed
2
3## Fast mode
4
5Codex offers the ability to increase the speed of the model for increased
6credit consumption.
7
8Fast mode is currently supported on GPT-5.4. When enabled, speed is increased
9by 1.5x and credits are consumed at a 2x rate.
10
11Enable it by typing `/fast`. It’s available in Codex IDE Extensions, Codex
12CLI, and the Codex app when you sign in with ChatGPT. With an API key, Codex
13uses standard API pricing instead and you can’t use `/fast`.
14
15[
16Your browser does not support the video tag.
17](/videos/codex/fast-mode-demo.mp4)
18
19## Codex-Spark
20
21GPT-5.3-Codex-Spark is a separate fast, less-capable Codex model optimized for near-instant, real-time coding iteration. Unlike fast mode, which speeds up GPT-5.4 at a higher credit rate,
22Codex-Spark is its own model choice and has its own usage limits.
23
24During research preview Codex-Spark is only available for ChatGPT Pro subscribers.